Safety device for dial transfer cams

ABSTRACT

A dial transfer cam safety device for a circular hosiery knitting machine that includes a toe closing apparatus. The device is provided with a mechanism for suppressing the selected movement of the transfer cam into operating engagement with the butts of transfer bits should said butts be out of alignment for receiving the cam when entering that cycle of closing the toe of the knitted hosiery article being formed.

United States Patent [1 1 Imboden 1 SAFETY DEVICE FOR DIAL TRANSFER CAMS [75] Inventor: Walter Imboden, Wyomissing, Pa.

[73] Assignee: Rockwell International Corporation,

Pittsburgh, Pa. 22 Filed: May 18, 1972 Appl. N0.: 254,443

[52] US. Cl 66/95, 66/21, 66/26 [51] Int. Cl D04b 15/02 [58] Field of Search 66/95, 26, 21, 173

[5 6] References Cited UNITED STATES PATENTS 3,513,667 5/1970 Billi 66/95 1,361,291 12/1920 Stibbe 66/95 Feb. 12, 1974 3,225,569 12/1965 Luchi .l 66/95 FOREIGN PATENTS OR APPLICATIONS 125,077 11/1967 Czechoslovakia 66/95 4/1965 ltaly 66/95 Primary ExaminerJames Kee Chi [57] ABSTRACT A dial transfer cam safety device for a circular hosiery knitting machine that includes a toe closing apparatus. The device is provided with a mechanism for suppressing the selected movement of the transfer cam into operating engagement with the butts of transfer bits should said butts be out of alignment for receiving the cam when entering that cycle of closing the toe of 'the knitted hosiery article being formed.

2 Claims, 4- Drawing Figures 1 SAFETY DEVICE FOR DIAL TRANSFER CAMS BACKGROUND OF THE INVENTION The invention pertains to a safety device for the dial transfer cam of a circular hosiery knitting machine as, for example, one of the types shown in US. Pat. No. 3,205,683 and which includes a toe closing apparatus such as is disclosed in U.S. Pat. No. 3,575,019.

In the forming of an article of hosiery on a knitting machine of the type described in the above mentioned patent, the complete article is formed beginning with the double-ply welt portion and ending with the closing of the toe portion.

As is well known to those conversant in the knitting art, the transfer bits carried in the dial are operated in cooperation with the cylinder needles to form the welt portion. During the knitting of the leg portion the dial is disengaged and the knitting proceeds by drawing the stitch loops over the so-called sinkers. Upon completion of the leg and foot portions, the toe closing in accordance with the'teachings of the above mentioned patent, a multi-ply toe portion is formed which again requires utilization of the transfer bits carried in the dial.

The closing'of the toe portion requires a twisting of the knitted article that is accomplished by a differential movement between the dial and cylinder of about 225 degrees and is achieved by means of the clutching apparatus forming a part of the dial drive.

To commence the toe closing operation the dial transfer cams are moved into operating position with the butts of the transfer bits and are effective in a known manner to either project or retract said bits within their respective dial slots. The transfer bits are usually devided into groups of four with one group having so-called high butts and the immediately adjacent group having low butts.

The dial transfer cams are moved selectively in two steps to act on the high butts during the first step and then upon all of the transfer bits during the second step. To act on the high butts during the first step, the cam is moved into operating position only when said cam is overlying a group of low butt transfer bits.

Immediately after the commencement of the toe closing operation, the dial transfer cams must be temporarily moved to their inoperative position to obtain the required twist in the knitted article by means of the differential movement between the dial and cylinder as described above.

When the required amount of twist has been obtained the dial transfer cams are again selectively moved to their operating position to complete the toe closing operation.

At this point in the knitting cycle, .difficulty hasbeen encountered when the dial transfer cams are again caused to move to their active position. The clutching apparatus forming a part of the dial drive referred to above serves to interrupt rotative movement of the dial at desired times during the knitting cycle, such for example as to effect the differential movement between the dial and cylinder referred to above. Should this clutching apparatus re-engage the dial drive so as to cause the dial to be misaligned relative to its normal operating position, the dial transfer cams when selected would overlie the high butts of the transfer bits. The se lective movement of the transfer cams under such a condition would force the latter into contact with the high butts of the transfer bits creating what is referred to as a smash having definite damaging results to either or both the dial and the transfer bits.

The safety device for dial transfer cams according to the present invention has eliminated the possibility of a smash in the event of a possible misalignment of the dial by providing a means which will suppress the full selected movement of said cams when they overlie the high butts of the transfer bits. This suppressing means will automatically permit full selected movement of the cams after the dial has moved a sufficient distance to bring the transfer bits having low butts into alignment with said cams.

SUMMARY OF THE INVENTION The safety device for dial transfer cams comprising the invention forms a part of the operating linkage for selectively moving said cams into operating engagement with the butts of the transfer bits slidably carried in the dial. This operating linkage is provided with a compressible coupling and in the event of misalignment of the dial as previously described, the transfer cams when selected will move a distance which will place them in contact with the upper surfaces of the high butts on the transfer bits. When reaching this position further movement of the cams is suppressed by the compressible coupling and they simply ride over the upper surfaces of the butts until the transfer bits having low butts come into alignment with the cams. When the a dial has moved a sufficient distance to bring the transfer bits with low butts into alignment with the earns, the biasing force of the compressible coupling returning to its initial uncompressed state is effective in completing the selected movement of said cams to their operating position.

It is a general object of the invention to provide a safety device for the dial transfer cams of a knitting machine for suppressing their selected movement when the butts of the dial transfer bits are not in proper operating position.

A further object is to provide a safety device for the dial transfer cams ofa knitting machine which is of inexpensive and simplified construction, requires a minimum amount of space to perform its intended function and which is readily applicable to existing machines.

These and other objects of the present invention will become more fully apparent by reference to the appended claims and as the following detailed description proceeds in reference to the figures of drawing wherein:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in side elevation of a'circular knitting machine to which the safety device for dial transfer cams has been applied;

FIG. 2 is a top view of a portion of a knitting machine as seen looking in the direction of the indicating arrows of line 2-2 in FIG. 1;

FIG. 3 is a perspective view in exploded form showing the dial mechanism of the knitting machine and the manner in which the transfer cams are operatively associated therewith, and

FIG. 4 is a sectional view in side elevation of the compressible coupling according to the invention for suppressing the selected movement of the dial transfer cams.

DESCRIPTION OF THE PREFERRED EMBODIMENT As the general construction and operation of a circular hosiery knitting machine is known and familiar to those conversant in the knitting art, and as the invention is entirely concerned with a safety device for dial transfer cams applicable to such machines, it is only considered necessary here to illustrate and describe those parts of such a machine directly concerned with a preferred form of the present invention.

Referring to FIG. 1 of the drawings a portion of a knitting machine of the type to which the invention is applicable is shown having a supporting structure in which is mounted a needle cylinder 11 having the usual slots 12 in which needles 13 are slidably carried.

A single conventional sinker is shown at 14 and is representative of the type adpated to function in cooperation with the needles 13.

A dial apparatus generally identified by numeral 15 is disposed immediately above and in close proximity with the needle cylinder 11 and by a drive means not shown, but well known in the art is caused to be rotated with and on the same axial center as the cylinder 11. The dial apparatus consists of two principal elements, namely, a dial bed 16, which as shown in FIG. 3 is provided in its upper surface with a circumferential series of radially extending slots 17 within each of which is slidably carried a dial transfer bit 18, and a dial cap 19 having cam means yet to be described for effecting radial movement of said transfer bits 18.

The dial cap 19 is provided with a centrally disposed and upwardly directed necked portion 20 having on its outer surface a pair of machined planar surfaces 21 and 22 (FIG. 3). These planar surfaces 21 and 22 provide a means for slidably mounting a pair of dial transfer cams 23 and 24 respectively to the dial cap 19. These transfer earns 23 and 24 are basically alike and for purpose of brevity, FIG. 3 shows details only of transfer cam 23. As shown in FIG. 3 the dial transfer cam 23 includes an integrally formed and upwardly directed support bar 26 having a centrally disposed slot 27 that extends for a distance nearly the full length of said bar. A slotted cap member 28 serves to attach the transfer cam 23 to the planar surface 21 by means of screws 29 passing through openings 30 in said cap and with their threaded portions assembled in a pair of aligned threaded holes 31 in said planar surface 21.

In assembled position on the planar surface 21 cap member 28 permits the transfer cam 23 to be moved vertically within the limits of slot 27 of its support bar 26.

The transfer cam is provided with a biasing means which continually urges it in an upwardly direction to a non-operating position and must be selectively moved to its operating position by a means to be more fully described. This biasing means includes a coil spring 32 which is adapted to assemble in a vertically extending hole 33 formed in the necked portion 20 of the dial cap 19 with one side thereof being open to and communicating with the planar surface 21 as at 34. A pin member 35 protruding from and fixed in the support bar 26 adjacent its upper end is adapted to engage the upper surface of spring 32 which is effective in urging the transfer cam 23 toward its non-operating position.

When selectively moved to its operating position the transfer cam 23 is pushed downwardly and is caused to enter an opening 36 in the dial cap 19 to act upon the butts of the transfer bits 18. As heretobefore described the transfer bits 18 are divided into groups with alternate groups having high butts and the intermediate groups having low butts. In FIG. 3 two transfer bits 18 are shown with a high butt on one being identified by numeral 62 and the other with a low butt that is identified by numeral 63.

The transfer cam 23 is selectively moved to its operating position by cam controlled actuating linkage which receives its dictates from a cam 37 (FIG. 1) carried on the main cam drum 38. A cam follower 39 fixed to the end ofa double armed lever 40 transmits the dictates of cam 37 to a second double armed lever 41 and it in turn pushes a vertically disposed actuating rod 42 upwardly causing a third double armed lever 43 operatively associated therewith to pivot in a manner causing its end 44 to move downwardly. End 44 of lever 43 is positioned so as to bear upon the upper surface 45 (FIG. 3) of the support bar 26. This downward movement of the end 44 of lever 43 pushes the support bar 26 in a like direction causing the transfer cam 23 to be selectively moved to its butt engaging or operating position.

The safety device for dial transfer cams comprises a compressible coupling that is identified generally in FIGS. 1 and 4 by numeral 46. This compressible coupling functions in cooperation with the actuatingrod 42 and includes a cylindrical sleeve 47 that is adopted to slidably assemble on the upper end portion of said rod 42.

The upper end of the sleeve 47 as fixed thereto, by any suitable means, an upwardly directed threaded extension 48 which is adapted to extend through an aperture 49 provided in that end oflever 43 opposite its end 44. A pair nuts 50 and 51 assembled on the extension 48 as shown in FIGS. 1 and 3 serve to connect lever 43 to the actuating rod 42 and also provides an obvious means for adjustment thereof. A collar member 52 is fixed to the lower end of the sleeve 47 having a centrally disposed opening 53 through which the actuating rod 42 extends. This collar member 52 also includes a pair of spaced threaded holes within which the threaded ends of two shouldered screws 54 and 55 are adapted to assemble. Screws 54 and 55 extend downwardly in a plane parallel with the axis of the actuating rod 42 and extends through aligned apertures 56 and 57 respectively provided in a collar 58 that is fixed to said actuating rod 42 by means of set screws 59 (FIG. 1). Compressible type coil springs 60 and 61 assemble on screws 54 and 55 respectively intermediate the collars 52 and 58. At assembly springs 60 and 61 are slightly compressed and with the heads of the screws 54 and 55 being in contact with the underside of collar 58, the pre-set tension on the springs is sufficient to permit the compressible coupling 46 and actuating rod 42 to serve as a single rigid element for selectively moving the transfer cam 23 into its operating position. If an interference is encountered however springs 60 and 61 will be further compressed permitting the actuating rod 42 to move upwardly within the sleeve 47 without further pivoting movement of lever 43.

To summarize the operation, the dial transfer cams are selectively moved into operating engagement with the butts of the dials transfer bits during the formation of the welt portion of an article of hosiery. During the formation of the leg and foot portions of a stocking the transfer cams are inactivated and then re-selected to operating position to form and close a multi-ply toe portion. Immediately after commencement of the toe closing operation, the transfer cams must be temporarily moved to their inoperative position so as to permit the heretofore described differential movement between the dial and cylinder so as to obtain a predetermined amount of twist upon the knitted article required by the toe closing apparatus. After the twisting of the knitted article, the transfer cams are caused once again to move to their operating positions. During the interval of twisting the article and the reselection of the transfer cams, should a misalignment of the dial occur relative to its normal operating position, said cams will move into contact with the high butts 62 of the transfer bits 18. In this event further movement of the cams is suppressed through compression of springs 60 and 61 of the compressible coupling and said cams simply maintain contact with the upper surface of the high butts until the dial has moved a sufficient distance to place the transfer bits having low butts 53 in alignment with said cams. When the transfer bits having low butts come into alignment with the transfer cams springs 60 and 61 will return to their initial state and pivot lever 43 the distance necessary to complete the selective movement of said transfer cams.

Although the present invention has been described in connection with a preferred embodiment it is to be understood that modifications and variations may be resorted to without departing from the spirit and scope of the invention as those skilled in the art will readily understand. Such modifications and variations are considered to be within the purview and scope of the invention and the appended claims.

I claim:

1. In a knitting machine having a needle cylinder with needles slidably carried therein and a transfer dial including transfer bits with operating butts which are radially movable by a transfer cam operatively associated with the transfer dial, the improvement comprising means for moving said transfer cam to and from a position of operating engagement with the butts of said transfer bits, said moving means including compressible coupling means for suppressing movement of said transfer cam toward said'transfer bits when the butts of the latter are not in position to receive the dictates thereof.

2. The knitting machine according to claim 1 wherein said compressible coupling means includes a plurality of coil spring members operatively connected thereto. 

1. In a knitting machine having a needle cylinder with needles slidably carried therein and a transfer dial including transfer bits with operating butts which are radially movable by a transfer cam operatively associated with the transfer dial, the improvement comprising means for moving said transfer cam to and from a position of operating engagement with the butts of said transfer bits, said moving means including compressible coupling means for suppressing movement of said transfer cam toward said transfer bits when the butts of the latter are not in position to receive the dictates thereof.
 2. The knitting machine according to claim 1 wherein said compressible coupling means includes a plurality of coil spring members operatively connected thereto. 